“Even if they do not necessarily achieve the goals that they posit, they make a positive difference in the world,” she said.

Davis, a nationally known civil rights activist and scholar, spoke as part of the Marquette Forum, a yearlong series of discussions examining racism and inequality.

Marquette’s invitation to speak drew criticism from the right on Twitter.

And the irony of being asked to speak at Marquette, which removed a mural of another black activist, Assata Shakur, in 2015, was not lost on Davis. Davis was once labeled a terrorist by President Richard Nixon. After massive demonstrations, she was acquitted of criminal charges related to a prison break in 1972.

Shakur, meanwhile, was convicted of several felonies in 1977 after a police officer was fatally shot in New Jersey. She escaped from prison and gained political asylum in Cuba. Davis, who called Shakur a “friend and comrade,” asserted that the evidence against Shakur, like the evidence in her own case, lacked credibility.